Alert archive / Florida / Freeze Warnings in 2021

Freeze Warning 2, NWS Jacksonville, FL

January 16, 2021Alachua County, Bradford County, Nassau County, Florida

NWS Jacksonville, FL issued this freeze warning at Jan 16, 2021, 1:49 PM EST for Alachua County, Bradford County, Nassau County, Florida. It took effect at Jan 17, 2021, 1:00 AM EST. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jan 16, 2021, 1:49 PM EST (18:49 UTC)
In effect from
Jan 17, 2021, 1:00 AM EST
Expired
Jan 17, 2021, 8:56 AM EST
In force
8 hr
Issued by
NWS Jacksonville, FL

Counties Alachua County, FL, Bradford County, FL, Nassau County, FL

The radar

The Jacksonville radar (KJAX), 59 km from the middle of the area, began a volume at 18:48 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 6.8 hours before the alert went out and 61 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 12:00Z on 2021-01-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Jacksonville, FL at 12:00Z on 2021-01-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -105 square meters per square second.1939587897117136156Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2105 m above ground
0-6 km bulk shear
111 kt
0-1 km storm-relative helicity
-105 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

676 
WWUS72 KJAX 161849
NPWJAX

URGENT - WEATHER MESSAGE
National Weather Service Jacksonville FL
149 PM EST Sat Jan 16 2021

FLZ024-025-031-032-136-236-171400-
/O.UPG.KJAX.FZ.A.0002.210117T0600Z-210117T1400Z/
/O.NEW.KJAX.FZ.W.0002.210117T0600Z-210117T1400Z/
Inland Nassau-Inland Duval-Bradford-Clay-Eastern Alachua-
Western Alachua-
Including the cities of Ratliff, Hilliard, Kings Ferry, 
Bryceville, Normandy, Ortega, Riverside, San Marco, Starke, 
New River, Doctors Inlet, Lakeside, Bellair, Middleburg, 
Orange Park, Gainesville, Gainesville Airport, Newnans Lake, 
High Springs, Newberry, and Archer
149 PM EST Sat Jan 16 2021

...FREEZE WARNING IN EFFECT FROM 1 AM TO 9 AM EST SUNDAY...

* WHAT...Sub-freezing temperatures as low as 31 expected. Frost is 
  also expected.

* WHERE...Inland Nassau, Inland Duval, Bradford, Clay, Eastern 
  Alachua and Western Alachua Counties.

* WHEN...From 1 AM to 9 AM EST Sunday.

* IMPACTS...Frost and freeze conditions could kill crops and 
  other sensitive vegetation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Appropriate action should be taken to ensure tender vegetation
and outdoor pets have adequate protection from the cold
temperatures. Young children, the elderly and the homeless are
especially vulnerable to the cold. Take measures to protect them.

&&

$$

FLZ033-037-038-124-125-133-138-140-240-340-171400-
/O.CON.KJAX.FR.Y.0002.210117T0600Z-210117T1400Z/
Inland St. Johns-Putnam-Inland Flagler-Coastal Nassau-
Coastal Duval-Coastal St. Johns-Coastal Flagler-Eastern Marion-
Central Marion-Western Marion-
Including the cities of Fruit Cove, Switzerland, Bakersville, 
Picolata, Bostwick, Carraway, Palatka, Bunnell, Espanola, 
Andalusia, Amelia City, Fernandina Beach, Yulee, Arlington, 
Jacksonville, Oceanway, Tallyrand, Ponte Vedra Beach, Durbin, 
Palm Valley, Anastasia, Saint Augustine, Palm Coast, Lynne, 
Moss Bluff, Anthony, Burbank, Ocala, Weirsdale, and Ocala Airport
149 PM EST Sat Jan 16 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM EST
SUNDAY...

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

* WHERE...Eastern Marion, Coastal Nassau, Coastal St. Johns, 
  Central Marion, Western Marion, Putnam, Inland Flagler, 
  Coastal Duval, Inland St. Johns and Coastal Flagler Counties.

* WHEN...From 1 AM to 9 AM EST Sunday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
1 follow-up statement
948 
WWUS72 KJAX 171356
NPWJAX

URGENT - WEATHER MESSAGE
National Weather Service Jacksonville FL
856 AM EST Sun Jan 17 2021

FLZ024-025-031-032-136-236-171500-
/O.CAN.KJAX.FZ.W.0002.000000T0000Z-210117T1400Z/
Inland Nassau-Inland Duval-Bradford-Clay-Eastern Alachua-
Western Alachua-
Including the cities of Ratliff, Hilliard, Kings Ferry, 
Bryceville, Normandy, Ortega, Riverside, San Marco, Starke, 
New River, Doctors Inlet, Lakeside, Bellair, Middleburg, 
Orange Park, Gainesville, Gainesville Airport, Newnans Lake, 
High Springs, Newberry, and Archer
856 AM EST Sun Jan 17 2021

...FREEZE WARNING IS CANCELLED...

$$

FLZ033-037-038-124-125-133-138-140-240-340-171500-
/O.CAN.KJAX.FR.Y.0002.000000T0000Z-210117T1400Z/
Inland St. Johns-Putnam-Inland Flagler-Coastal Nassau-
Coastal Duval-Coastal St. Johns-Coastal Flagler-Eastern Marion-
Central Marion-Western Marion-
Including the cities of Fruit Cove, Switzerland, Bakersville, 
Picolata, Bostwick, Carraway, Palatka, Bunnell, Espanola, 
Andalusia, Amelia City, Fernandina Beach, Yulee, Arlington, 
Jacksonville, Oceanway, Tallyrand, Ponte Vedra Beach, Durbin, 
Palm Valley, Anastasia, Saint Augustine, Palm Coast, Lynne, 
Moss Bluff, Anthony, Burbank, Ocala, Weirsdale, and Ocala Airport
856 AM EST Sun Jan 17 2021

...FROST ADVISORY IS CANCELLED...

$$

The office that day

Everything else NWS Jacksonville, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 16, 2:56 AM ESTFrost AdvisoryJAXDuval, Flagler, Marion, Nassau30 hr
Jan 16, 2:56 AM ESTFreeze WatchJAXAlachua, Bradford, Nassau11 hr

Nearby

Freeze Warnings in Florida, 2021Every freeze warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.